Heterogeneous in-reactor polymer blends
US8106127B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 2009 |
| Grant date | Jan 31, 2012 |
| Priority date | — |
| Expiry date | Dec 15, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L2314/06
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
An in-reactor polymer blend comprises (a) a propylene-containing first polymer; and (b) an ethylene-containing second polymer such that the polymer blend comprises between about 50 wt % and about 80 wt % units derived from ethylene and between about 50 wt % and about 20 wt % units derived from propylene. The blend is substantially free of dienes and the content of ethylene in the second polymer in the form of ethylene-ethylene-ethylene triads is at least 40%. The second polymer contains at least 0.1 branch having 8 or more carbon atoms per 10,000 carbons. In addition, the blend has a strain hardening index of at least 1.8, a shear thinning slope in the plot of log(dynamic viscosity) versus log(frequency) of less than −0.2 and exhibits at least two peaks when subjected to Differential Scanning Calorimetry (first melt) corresponding to a first melting point of at least 150° C. and a second melting point of at least 40° C. such that the difference between the first and second melting temperatures is at least 20° C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.